Duplex triode vacuum tube



ATTORNEY s. M. KINTNER DUPLEX TRIODE VACUUM TUBE Filed Aug. 28. 1924 May 10, 1932.

. SAMUEL M. KINTNER, o F PITTSBURGH, rnNNsYLvANIA, Assreivoza 'ro Wnsfrnvefnousr;l

l l-MyA invention relates to thermionic dis`4 Patented May 10, 1932 ,ELECTRIoa MANUrAGTnRINGcoMPANY; A oonronA'rro'N or `PENN sYLvA`1vIA'- 'DUrLEXfrRo'nE VACUUM TUBE i Appiicano'n meafaugust as, 1924.4 serizn`11s1o.-'maevar chargeudevices andn more particularly to .a thermionic triode: having iarelatively large capacityi A f- M `1 An object of my invention' is to produce a space discharge device having a filamen tary cathode adapted to-.be-heated byllow voltage and smallAcurrent-and have `alarge electron emission.

Another obJect Vof my inventionis to Vpro-V duce a'space discharge :device having lowcurrent, low-voltage ilamentary cathodes and a plurality of anodes.` l

Another object of my invention is to pro-v duce a space discharge devicehaving a-fplu` rality of electrodes connected in parallel..` f

Another object of-=my inventionisto pro.

duce a space dischargedevi'ce'havinga plurality `of cathodes serially connected and a plurality of anodes parallelly connected'.-

Another object of my invention is to. profduce a space-current discharge device having the same operating characteristics and made from the same parts as a standard-:type of tube and having ahigherspace current.

Another objectot my invention is, to pro;y duce a space-current discharge device having. a relatively high space current and. 'utilizino' in its construction, parts similar to e C 'u those of prevlousstandard construct1on.

Another object of my invention is tofproduce a space discharge device having a high mutual conductance and a low inter-electrode capacity.

Another object of myinvention is to'prol duce a multiple arrangement of anodes,grids and cathodes mounted on a small numberA of press Wires.

In the prior art `of the manufacture Aof 'vacuum tubes, it has beenl found'desirablje tol construct a thermionic'triode' having afilamentary cathode of such a size and constitution that it could be heated to an operating temperature by the current of a single dry cell.. In the construction of such adevic'e; it has'been found that the electron emission of a filamentary cathode suthciently'smallto be heated to a Working temperature by Ythe current from a single dry cell was limited tov a-relatively small :value y .For many ipurposes, xthis value has been` found l-to be too small.'V For some of: these purposes, 1t has been possible .to utilize theV space current LofytWo-.devices in parallel,

Y thereby; obtaining a s uiiiciently f large anode current.` -'Tliishowever, 'has not been 'Wholly satisfactory because of `the' difficulty of conf A structing tubesjvvhose performance characf` teristics 'are nearlyenough alike to permit the-nieto operate in parallel.- Much carei'ny choosing and 'matching-the,tubes has been necessary to .find pars.- of v tubes that WouldnA operate. inparallel, 'or elaborate connectionl schemes havebeennecessary to cause tubesof-j.

differentcharacteristics tozoperate in parallel. This difficulty haslloeen due more to dif-` erences'invacuum than to any other factors since it'has been foundv thatI it is quite'` pos-d sible'fto 4construct the Amechanical portions to the same dimensions with adequateV accuracy'.v r Myinvention sprovides Ameans v whereby al spacev discharge device is produced having a cathode suitableY for heating by dry-battery current and having thejdesired high electron stream and plate'ourrent. invention 'con-` sists of a structure comprising afplurality ed upon single: lead; Wires in a-"single pressl Within a single containern InV mypreferred em'bo'dl'ment, `Iuse a pair of cylindrical anodes, fa pairo cylindrical' grids and a pair ojilamen'ts, alllof `the size, material andstructure Well known 'the prior art Other'objects andV structural details of my invention will be apparent rornvthe ifollwv-y the accompanying drawings, Wherein j Figurelf is a view, partially in elevation and partially in section, of a thermionc discharge device structure having a disposi.- tion of the plane containing; the axes or' the Vof cathode,ano'de andv grid electrodes `mount-` Ving description when readin connection with cylindrical anodes; atright angles to 'tlie plane of the press.

,Fig-.V 2'1sa v levv, partially inelevationfand" partially section, of a `structure havingthe plane of the axes of the cylindrical anodes parallel tothe plane of the press,

^ VFig, Sasa View in ,horizontal sectionvoff loc entrant stem portion Ziterminating in a pressi 5 through y which are sealed a plurality of lead wires 6. Lead wires G are attached to. terminals 3. Within container 1, and 'upon lead wires 6 are mounted a pluralty of electrodes comprising a pair of cylindrical anodes 7 and 7, a pair'of cylindrical helical grids'8- and 8. and a pair ofr filamentary cathodes 9 and 9. f

Anodes 7` and 7 are cylindrical in form,

each with a lin 11 at a place onits periphery extending the length of thecylinder. vThe fins 11 are attached to one of the Wires 6 which are sealed in the press 5. Helical grids 8 and 8 are attached to supporting wires 12 andf12 which, inturn, are attached toanother of they Wires 6 through press 5. The Wirev 6' to lwhich the fins 11 of anodes7 andl 7 are at-l tached has, upon the end within container 1,A

a glass bead 14 through'which Yis sealed ya supporting and lead Vrwire 15. The free ends of Wire 15 supportthe upper ends of'lamentary cathodes 9 and 9, the `lowerends of which are attached lto others-ofxwires 6;

By means of the construction shown `in the drawings and described', a pair ofanodes is mounted upon azsingle lead'wirefthrough press 5 and electrically connectedthereto. A pair of'g'rids is likewise mounted upon another wire 6 and electrically connected thereto. The pair of anodes is connected in parallel as is the pair of grids- The pair of fila'- mentary cathodes 9 and 9 is connected in series through the intermediary of Wire 15. The structure as shown and described is further completed by-evacuation'of air from container 1 through a tip seal 16.

In the operation of my device, filamentary cathodes 9 and 9 may be heated by current from dry batteries to a temperature at which they emit electrons. An electron rstream will then flow upon the application of voltage between the anode and the cathode. The electron streams between the cathode .9 and anode 7 and between cathode 9 and anode 7 are then parallel. The device thereby has a space current twice as great as would occur in a similar construction containing a single anode and cathode ofthe same size and type when the cathode was heated to a` corresponding temperature and Va similar'voltage applied between cathode and anode.v Furthermore, the vacuum surrounding both anodes, both cathodes and both grid-electrodes is 'the same and, therefore, the operating characteristics of thek twosets of electrodes are the same in response to changes in applied po- I tential and changes of grid potential.

By thel structure described, I have produced a space current device in which a greater electron stream is obtainable and a greater anode current obtainable than in similar devices of the prior art.`

. In the modification of my invention shown in F igs. and 5, the anode cylinders 8 and 8" are disposed in theplane of the press 5, the construction of the tube being otherwise similarto that' shown in Figs. 1, 3 and 4. However, Vthe latter construction, with the anode cylinders arranged vin a plane perpendicular to the plane of the press, is deemed preferable since it rsultsin a simpler arrangement of the wire standard extending from the-pressto support the severalv electrodes, and'reduces the interelectrode capacity of the tube. yIn: both constructions, however, the two; sets` of distinct electrode assemblies are positioned by the standards extending fromonly four leadin wires which arefusedin the. press.y The latter feature becomes very importantin .the

construction of-smalltubes,1since difficulties l are encountered when making presses havev lng fused thereto more than four wires. VThe sov small number of press Wires is, of course,veryimportantinl soffar as. it-aifefcts thegintervelectrode capacity-of the tube. f

VVhileIhavel shown only two embodiments Y of my: inventionv in the. accompanying drawings, it is 'capable-of various changes and modificationsv without vdeparting -from Vthel spirit thereof, and it is desired, therefore, that only ,such limitations shallv be imposed thereon as are indicated in thepriorart or in theppendedclaims. f- 4 I 1 I claim as'vmy invention: p I A v 1. Anl electron-discharge de vicel comprisinga flat press, a plurality of lead-in'wires heldv in said press, and al plurality of sets of' electrodes, each'set comprising a cathode and an anode, each anode surrounding'itsrespective cathode and all having their central axes disposed in a plane perpendicular to thc planeof said press.' A i i 'j Q. An Aelectron-discharge device comprising a container, and a plurality ofano'de, gri-d and cathodefelements assembled'in a plurality'of distinct parallel disposed sets, the central axes of said elements beinginf one,plane,fa press disposed in a plaine perpendicular tozsaid one plane,`and a plurality of Awires extending fromv said/press for supporting -said electrode sets and for making electrical connections therewith.

3. In an evacuated electron-discharge de vice, a pair of anodes, cathodeelements and l los four lead-iii Wires sealed into said stein andV having extensions projecting into said container, a pair of cathode elements, distinct grid elements surrounding each cathode element, anode elements surrounding' said cathode and gridV elements and constituting therewith distinct electron-discharge paths, the extensions of three of said Wires constituting the supports for said cathode elements, the extensions of tivo of said Wires constitutingthe sole supports of said anode and grid elements.

6. An electron-discharge device comprising a container having a press, a pair of parallel disposed tubular anodes, a pair of cylindrical grids and cathodes, respectively disposed Within said anodes, and four leadingin Wires sealed into said press and constituting the sole mechanical support, and the electrical connections, of said anode, grids and catliodes. l

7. In an electron-discharge device, a pair of parallel standards, a pair of longitudinally extending cathode elements disposed in a plane perpendicular to the plane of said standards, a pair of grids individually1 surrounding eachof said cathode elements, and tubular anode means surrounding said grids, said standards constituting the only supports for said grids and anodes.

8. An electron-discharge device comprising a press, a pair of longitudinally extending cathode elements disposed ina plane perpendicular to the plane of said press, a pair of grids, each grid surrounding only one of said cathode elements. tubular anode means surrounding said grids, and lead-in Wires extending from said press and connected to said electrodes.

9. In an electron-discharge device comprising a press, a pair of parallel tubular anodes Whose axes are disposed in a plane different from the plane of the press, cylindrical grids concentrically disposed Within said anodes, longitudinal cathode elements, centrally disposed Within said grids, a plurality of leadin Wires fused in said press, one of said leadin Wires being the common terminal connection of said anodes, another of said lead-in Wires being the common terminal connection of said grids, and still another of said lead-inV l0. An electron-discharge device comprising an evacuated envelopev having a pressv therein, an electrode having a'pluiality of' cylindrical portions, `a second electrode With-V in each ofsaid cylindrical portions and an l electrical conducting support-arm extending Y through said press and supporting said electrodes.

ll. An electron-discharge device comprising an evacuated envelope having a press' therein, an electrode having av plurality vof substantially cylindrical portions, a ilamentf` electrode Within each of said portions suhstantially concentric therewith and a sup- VWires being one of the terminal connections vof said cathode elements.

port-'arm Which extends from said press and i which is common toall of said electrodes and electrically connected to said first-mentioned electrode. p

l2. In `an electron-discharge device, an electrode having a plurality of V*cylindrical portions, a cathode Within each of said portions,

asupport-arm for said first mentioned electrode commonl to the portions thereof and means attached to said*support-arm supporting all of said cathodes.

13. An electron-discharge device comprising anl evacuatedenvelope having aV press therein, an anode-electrode having a plurality of cylindrical portionsa second electrode Within each of said cylindrical portions and a support-arm which extends from said press and which is common to all of said'electrodcs and electrically connected to said anode-electrode. A l

In testimony whereof, I have hereunto subioo i scribed my name this 22nd day of August,

1924. Y Y SAMUEL M. KINTNER. 

